arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 1208.4834cond-mat.str-elhep-th
收藏

Genons,扭曲缺陷和投影非阿贝尔编织统计

Genons, twist defects, and projective non-Abelian braiding statistics

Maissam Barkeshli, Chao-Ming Jian, Xiao-Liang Qi

摘要:

最近已经认识到,通过引入非本征缺陷,例如在常规量子霍尔态或拓扑绝缘体中的晶格位错或超导体-铁磁畴壁,可以在常规拓扑态中产生一般类别的非阿贝尔缺陷。在本文中,我们首先将这些缺陷与拓扑状态的对称性相关的外在扭曲缺陷的更广泛的概念方案。我们明确地研究了几类例子,包括$Z_2$和$Z_3$扭曲缺陷,其中具有N扭曲缺陷的拓扑状态可以映射到一个拓扑状态没有扭曲缺陷的属$g \propto N$表面。为了强调这种联系,我们把扭曲缺陷称为基因子。我们开发的方法来计算的genons的投影非阿贝尔编织统计,我们发现编织是由绝热模变换,或Dehn扭曲,有效的亏格g表面上的拓扑状态。我们研究这个投影编织统计和普通的非阿贝尔编织统计之间的关系时,基因子成为deconfined,有限能量激发。我们发现,编织一般是不同的,在马约拉纳的情况下,这打开了根本上新颖的行为的可能性。我们发现的情况下,基因具有量子维2,可用于通用拓扑量子计算(TQC),而主机拓扑状态本身是非通用的TQC。

英文摘要:

It has recently been realized that a general class of non-abelian defects can be created in conventional topological states by introducing extrinsic defects, such as lattice dislocations or superconductor-ferromagnet domain walls in conventional quantum Hall states or topological insulators. In this paper, we begin by placing these defects within the broader conceptual scheme of extrinsic twist defects associated with symmetries of the topological state. We explicitly study several classes of examples, including $Z_2$ and $Z_3$ twist defects, where the topological state with N twist defects can be mapped to a topological state without twist defects on a genus $g \propto N$ surface. To emphasize this connection we refer to the twist defects as genons. We develop methods to compute the projective non-abelian braiding statistics of the genons, and we find the braiding is given by adiabatic modular transformations, or Dehn twists, of the topological state on the effective genus g surface. We study the relation between this projective braiding statistics and the ordinary non-abelian braiding statistics obtained when the genons become deconfined, finite-energy excitations. We find that the braiding is generally different, in contrast to the Majorana case, which opens the possibility for fundamentally novel behavior. We find situations where the genons have quantum dimension 2 and can be used for universal topological quantum computing (TQC), while the host topological state is by itself non-universal for TQC.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑